The FBT Mitus 118SA is a single 18 inch bass bin which delivers a great sound with alot of power. The FBT Mitus 118 SA produces 139db SPL from 1200 watts RMS. The Mitus 118SA is made from a birch plywood which helps the great sound be delivered from what is FBTs bass bin to match their FBT Mitus 152A which delivers the mid top you need to go with this bass bin.